Drink coffee. Save K-cups. Optional: you can rotate cups in Keurig coffee maker to punch additional drainage holes in bottom.
Step 2: Planter Cups
Remove foil lid, coffee grounds, and filter mesh. Wash out K-cups.
Step 3: Humidity Dome
Save and clean plastic display box from half-sheet cake. Use scissor or hobby knife to cut out small rectangle of plastic for ventilation door. Use scotch tape along top edge as a "hinge". Punch small hole in corner near bottom edge for temperature probe. Sharp cut from hole to bottom edge of clear dome may help with insertion of probe wiring so it does not interfere with clear plastic dome snapping in place.
Step 4: Temperature and Humidity
Small analog Temp/Hygrometer for reptile tank. Few dollars on eBay. Digital Heat Mat Thermostat extension plug from eBay or Amazon. Electric Household Heating Pad, waterproof.
Step 5: Planting Seeds
Dunk and squeeze Rapid Rooters plug or rock wool cubes in distilled water or very dilute hydroponic nutrient solution. Squeeze out excess water. Place in k-cups. Read seed planting info. Place 1-4 seeds inside hole. Tear off tiny corner bit of sponge and cover hole. Label and arrange k-cup planters on cake bottom lid. Carefully place lid on top of heating pad. Use cloth heat pad cover or thin towel between heat pad and bottom of cake tray.
Step 6: Set Up & Grow
Use 1 empty k-cup upside down to raise the temp/humidity gauge off the floor of germination station. Insert temp probe from heat mat thermostat. If suction cup present, use it to secure wiring in place so probe hangs down and insert it into an empty moistened Rapid Rooter plug and cup. Carefully place clear dome lid over tray bottom. Snap in only 1 or 2 corners. Set thermostat temperature (71-72 degrees F) and plug in heating pad power cord into thermostat. Turn heating pad ON to Medium power. Cover entire dome with dark towel or cloth to keep seeds in dark for initial germination period.